Electric bell



W. D. LUTZ.

ELECTRIC BELL.

I APPLICATION HLEp JULY 27,1917. 1,327,340. Patented Jan. 6, l920.

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WILLIAM D. LUTZ, OF ALLENDALE, NEW JERSEY.

ELECTRIC BIEIILJLI.

Specification of Letters Patent.

Patented Jan. 6, 1920.

Application'filed July 27, 1917. Serial No. 183,086.

To all whom it may concern:

Be it known that 1, WILLIAM D. Turn, a citizen of the United States, and resident of Allendale, in the county of Bergen and State of New Jersey, have invented a certain new and useful Electric Bell, of which the following is a specification.

hilly invention relates to electrically operated bells, and in its preferred form as herein shown, is especially designed for comparatively high voltage circuits. It may be used for example on 110 volt or 220 volt power circuits without external resistance.

An object of the invention is to provide an improved form of bell which is reliable in operation and economical in the use of current. The exact nature of the invention and the various features of novelty will appear more fully from the following detailed description and the appended claims.

Referring to the accompanying drawings, Figure 1 a front elevation of a bell adapted for use on direct current circuits, and embodying the principles of my invention, the cover section of the casing being removed. Fig. 2 is a sectional side elevation. Fig. 3 is a top plan View, the casing being shown in section. Fig 1 is a detail View showing a modified construction for use as a single stroke bell.

A pair of magnet coils 6 are mounted on cores 7 secured to a magnet frame 8. The cores may be clamped in the magnet frame by means of clamping screws 9, the magnet frame being drilled and slotted to receive them. Since the magnet spools fit tightly on the cores, no other provision is required to retain the spools and windings. The magnet and its accessories are mounted in a casing 11 having a removable cover section 12. The magnet frame may be secured in the casing by a fastening bolt 13.

A block 14 of insulating material, preferably asbestos wood, secured to the magnet frame, carries a pair of contacts 15. and 16, mounted on opposite sides of the block with their free ends projecting beyond the block and meeting at a common center. The

spring contact 16 is under tension tending to swing it downward away from the stationary contact 15, but is normally held up against the stationary contact by a comparatively large spring 17 on which is mounted an insulating button 18 bearing upward against the contact 16.

The armature 19 is pivoted at 20 to the magnet frame, and carries adjacent its free edge, a non-magnetic bearing block 21 (preferably a brass rivet) which rests on a steel rivet or block 29. carried by the spring 17. A striker 23 extends through the hollow fastening bolt 13 and is held up against the block 22 by a coil spring 24. The spring bears at its lower end againstthe bolt 13, and at its upper end against a ring 25 which may be sprung in a groove in the striker rod 23. A similar ring '26 serves to retain the striker in the bolt 13 when the latter is removed from the bell.

One end 27 of each of the coils 6 is connected to one of the line terminals 28. The other ends of these coils are connected respectively to the contacts 15 and 16, so that the coils are connected in series relation with each other. The only exposed live parts, exclusive of the line terminals, are the contacts and their holders and these become the equivalent of the neutral leg of the Edi son three-wire circuit, which inmost cities is grounded; therefore, the tendency of the current to jump to ground from the exposed live parts is reduced to a minimum. Also in case an accidental connection is made between the exposed live parts and the ground, the comparatively high resistance of the magnet windings will prevent a destructive current from flowing through the circuit established. 1

When the magnet coils 6 are energized the armature 19 is attracted and pulled down-r,

ward, causing the brass rivet 21 to press upon the steel rivet 22 in the spring 17, forcing the spring 17 downward. The upward pressure on the spring contact 16 is thereby removed, whereupon the contact spring straightens, separating the contacts, thus breaking the circuit and deenergizing the magnets 6 when the kinetic energy stored in the spring 17 will force the armature back and also reestablish the circuit. The armature 19 will after a few vibrations, be thrown back violently against a bumper spring 30 which will absorb the kinetic energy of the armature and return it on the forward stroke, thus conserving the energy imparted to the armature through the electromagnets and reducing the total amount of energy required to operate the bell. Each downward movement of the armature moves the striker 23 downward, causing it to strike the gong 31, the striker being returned by the spring 24 as the armature moves upward.

The construction of the parts is such that the striker does not remain in contact with the gong for any appreciable time, thus leaving the gong free to vibrate after being struck.

Fig. 4: shows a modification particularly designed to operate as a single stroke bell. A leaf spring 32 may be attached to the armature 33 for the purpose of holding the armature some distance from the magnet cores so that the armature may acquire sufficient momentum during its initial stroke to drive the striker against the gong with the necessary force to secure the desired loudness of tone.

For alternating current service the magnet cores may each comprise a bundle of iron wires forced into the spool and allowed to project from one end, the projecting ends bein clamped in the magnet frame by the screws 9 in the manner heretofore described. For alternating current service the contacts may be eliminated, if desired, and the armature allowed to vibrate in synchronism with the alternations of the current.

Modifications may be resorted to within the spirit and scope of my invention.

What I claim is 1. The combination of an electromagnet, an armature therefor moved in one direction by the magnet when the latter is energized, a' reciprocating member actuated by the armature, and an interponent between the armature and said member placed under tension by said movement of the armature and operable to return the armature.

2. The combination of an electromagnet, an armature therefor moved in one direction by the magnet when the latter is energized, a reciprocating member actuated by the armature, an interponent block formin a solid power transmitting medium between the armature and said member, and a spring carrying said block and operable to return the armature.

3. The combination of an electromagnet, an armature therefor moved in one direction by the magnet when the latter is energized, a reciprocating member actuated by the armature, an interponent between the armature and said member placed under tension by said movement of the armature and operable to return the armature, said member being free to move independently of said armature and interponent, and a spring to return the said member.

4. The combination of an electron'lagnet, an armature moved in one direction by the magnet when the latter is ener ized, a rod mounted for movement in the direction of its length, an interponent block between the armature and rod through which the movement of the armature is transmitted to the rod and the latter positively driven, a spring carrying said block and operable to return the armature when the magnet is deenergized, a: pair of contacts in the circuit of the magnet winding, said contacts normally held together by said spring, and means to separate said contact-s when the armature is actuated.

The combination with an electromagnet comprising a coil, a magnet frame and an armature, of a casing inclosing said parts, a hollow screw bolt securing the magnet frame to the casing, and a rod extending through said bolt and arranged to be moved in the direction of its length by the armature.

Signed at New York in the county of New York and State of New York this 12th day of July A. D. 1917.

WILLIAM D. LUTZ.

Vvitnesses HAZEL R. GATES, ERNEST L. GALE, Jr. 

